1. Field of the Inventions
The present inventions generally relate to an electronic remote control system of an internal combustion engine for a watercraft.
2. Description of the Related Art
Propulsion systems used for watercraft are conventionally operated using remote controls. For example, the shift and throttle operations of a propulsion system, such as an outboard motor, can be remotely controlled using a control lever of a remote controller provided in a steering console of the watercraft.
Such a remote control system is usually only configured to conduct the shift and throttle operations. For example, the shift operation is conducted with a throttle valve completely closed or in a so-called shifting range. The shifting range typically falls within a predefined range that generally defines a neutral position of a control lever. The throttle valve operation includes opening and closing of a throttle valve, for example, from a completely closed state to a full throttle state. The throttle operation is typically conducted with a shift state being maintained while in a so-called throttle range, which is a range beyond the above predefined shifting range of the control lever. In other words, the shift lever can move within a first range to control shifting and a broader second range to control the throttle.
The propulsion force of a small watercraft can be increased by installing two or three outboard motors on the stern. This modification can enable the watercraft to continue to operate even in the event of one motor failure. In addition, the watercraft can have a main steering console that is positioned at a center part of a watercraft, and an upper steering console that is positioned in a position higher than that of the main console. This configuration can provide a fine view, and is often integrated into a dual station type electronic remote control system. Such a system includes different remote controllers, which are connected to an electronic control unit of one or more of the outboard motors, and positioned in each of steering consoles to operate an outboard motor that can be installed far from a main steering console and an upper steering console (see, e.g., U.S. Pat. No. 6,280,269).